His mainly interest is dinosaur paleontology, so he has studied Late Jurassic dinosaurs of Portugal, but also worked in other reptiles (mosasaurs, plesiosaurs, crocodiles, turtles, etc.).
Published scientific articles, conferences proceedings, and book chapters that sum more than 100 publications since 1997.
Erected new taxa as the Lourinhanosaurus antunesi (1998), Dinheirosaurus lourinhanensis (1999),Tangvayosaurus hoffeti (1999), Draconyx loureiroi (2001) , Lusotitan atalaiensis (2003), Europasaurus holgeri (2006), Allosaurus europaeus (2006), Diceratus (2008), Microceratus (2008), Prognathodon kianda (2008), Miragaia longicollum (2009), Angolachelys mbaxi (2010), Angolatitan adamastor (2011), and Lusonectes sauvagei (2012).
He lives in Lourinhã, where he is engaged with the Museum of the Lourinhã, known for its important dinosaur collection. Since 1991, Octávio Mateus has organized dinosaur excavations in Portugal, where he collected many dinosaurs and other vertebrates, including sauropods, theropods, stegosaurs, crocodiles, and turtles.
Oneof his main scientific project is in Angola, where he discovered the first dinosaur from that country, in the scope of a paleontology project on vertebrates of Angola, the PaleoAngola Project, with geologists and paleontologists from Angola, Southern Methodist University (USA) and Natuurhitorisch Museum in Maastricht (Netherlands).
His interest for dinosaurs has taken him to the United States, Brazil, Greenland, Laos, Tunisia, Mozambique, Mongolia, Morocco, South Africa and Angola.
Since the age of four, Octávio has searched for dinosaur fossils with his parents co-founders of the Museum of Lourinhã. They raised Octávio in Lourinhã, an area rich in Late Jurassic dinosaurs and, very early in his career, Octávio excavated a dinosaur nest with them, finding embryos inside the eggs.
Topics of interest:
Paleontology of vertebrates, mainly dinosaurs.
Museology of natural history and paleontology.
Mechanisms of evolution and heterochrony.
Ontogeny and nanism in dinosaurs.
Late Jurassic Fauna
African paleontology, mainly Angola.
Global correlations in the Late Jurassic
Evolution and Darwinism